JP3408568B2 - Composite particles comprising semiconductor particles and conductive polymer, method for producing the composite particles, molded article of a composition containing the composite particles, and method for producing the molded article - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoconductive material whose conductivity is changed by light, or a conductive material such as a conductive coating liquid or film used for the purpose of antistatic, a light emitting material or an electrochromic material. Used as materials, optical switching elements, pressure-sensitive materials and ferroelectric materials that can detect changes in electrical resistance value due to pressure, or optical materials such as nonlinear optoelectronic materials that utilize phase conjugate wave generation and optical bistable phenomena. The present invention relates to a novel semiconductor / conductive polymer composite particle, a method for producing the same, a composition, a dispersion composition, and a method for producing the same.

[0002]

2. Description of the Related Art Needless to say, semiconductors are used in a wide variety of fields in the form of thin films and particles such as electronic component materials, optoelectronic materials, medical materials, catalyst materials, and sensor materials. Furthermore, by producing semiconductor particles called ultra-fine particles, which have a small particle size of 100 nm or less, specific properties not found in conventional bulk and particles are revealed,
Its application is being pursued. In other words, it is expected that electronic peculiarity due to small crystal space, chemical peculiarity due to large surface area with respect to volume, and appearance of graded material of component due to fine grain boundary will occur. . Forms that show electronically unique properties by forming small crystal spaces are thin films, rod-shaped,
Although it has a disk shape or the like, ultrafine particles are superior in isotropy of performance appearance to these forms.

As a method for producing semiconductor particles, generally, a method by mechanical pulverization, a vapor phase production method utilizing evaporation using heat or plasma, precipitation or hydrolysis is used. A known method is a liquid phase production method. These manufacturing methods are described in, for example, "Particle Handbook" (edited by Genji Jimbo et al., Asakura Shoten, 1991). The properties required for a particle material, particularly an ultrafine particle material, to have desired performance are different for each application, but the main points are: 1) The primary particles have a desired size. 2) The particle size distribution is narrow and all particles have uniform properties. 3) Does not contain aggregated particles. 4) Good storability. And so on. That is, the function as a particle to control the particle size and its distribution and to enhance their storage stability,
In particular, it is an important issue for expressing the unique function of ultrafine particles. Regarding ultrafine particles, several techniques have been proposed as a technique for controlling the particle size of nanometer size, for example, a method of narrowing the particle size distribution by using a protective colloid in the production in a liquid phase,
There is a method of collecting the produced particles from a predetermined place of the evaporation flame in the gas evaporation method in the gas phase. In addition, JP-A-4-1
As described in 89801, a method has been proposed in which an electron transfer agent and a monomer having an unsaturated bond are allowed to coexist in a solution, and semiconductor ultrafine particles are synthesized while being irradiated with light.

On the other hand, attempts have been made to synthesize composite particles composed of multiple components in order to make the particles highly functional. For example, Japanese Patent Laid-Open No. 279519/1990 discloses that specific silicone is added during the production of titanium hydroxide to prevent aggregation of fine particles. In addition, in Industrial Materials, Vol. 36, No. 14, p. 45 (1988), in order to improve storability and operability by surface treatment, the surface of TiO ₂ and Al ₂ O ₃ is added to the surface of titanium oxide particles. It has been proposed to form a treatment layer. Also, for example, the Journal of American Chemical Society 11
Volume 2, pp. 1327-1332 (1990) describes a method for producing ultrafine particles of a complex of cadmium selenide and zinc sulfide and physical properties.

However, the particles of the composites described in these examples are composites of an inorganic compound and inorganic compounds, and the composite particles of an inorganic compound and an organic compound are described in the above-mentioned Japanese Patent Laid-Open Publication No. There is almost no description except for 4-189801. Even the composite ultrafine particles of these inorganic compounds and organic compounds are composites for the purpose of improving particle size control and storage stability, and are expected to be particles of composites of inorganic compounds and inorganic compounds. It was not for creating optical and electronic functions by such compounding. Examples of the composite material of an organic compound and an inorganic compound, especially an organic compound and a semiconductor, include oxidation as described in Journal of American Chemical Society, Vol. 102, No. 16, 5137-5142 (1980). Many examples of photoelectrochemically modified electrodes are known, as seen in an example in which an electrode of titanium (n-TiO ₂ ) or tungsten oxide (n-WO ₃ ) is coated with a metal phthalocyanine thin film.

On the other hand, a photoelectric material obtained by forming an organic compound and an inorganic compound as a quantized composite thin film has attracted attention. For example, Application of Physical Letter (Appl. Phys. Lett), Vol. 61, No. 18,
(1992) said that copper phthalocyanine and titanium oxide (TiO _x ) were alternately formed into thin layers at a period of 10 nanometers, and photoconductivity several tens of times higher than that of a copper phthalocyanine single film appeared. . However, in order to form such a quantized thin film structure having a nanometer period, that is, a so-called superlattice structure, a precise vapor deposition method using an ion cluster beam or the like is required. In addition, a large number of repeating steps are required to form a device.

[0007] As the conductive polymer, in general, refers to those showing a ^{10-2 7} S · cm ^-1 degree or more conductive, and having a conductivity of metals comparable as polythiazyl, polyacene , Polyacetylene, and poly-p-
Iodine is added to main chain conjugated polymers such as phenylene, polyphenylene sulfide, polypyrrole, and polyaniline.
It is known that conductivity is improved by adding (doping) a small amount of an electron-accepting molecule such as arsenic pentafluoride or an electron-donating substance such as sodium, and polyvinylcarbazole, etc., whose conductivity is improved by light irradiation. . It is known that these conductive polymers are functional materials themselves, or have the property of changing color by desorption of a dopant or light irradiation, and are expected as various kinds of functional materials. However, many of these conductive polymers are synthesized by solid phase polymerization such as polyacetylene, and many are synthesized by electrolytic polymerization like many main chain conjugated polymers, and are It was not suitable for complex formation.

Further, as one of the methods for producing a conductive polymer, there is a method of chemically polymerizing using an oxidizing agent or the like, and as a method for producing ultrafine particles using a conductive polymer by this method, 50 to 250 nanometers are used. A method for producing polypyrrole fine particles having a particle size of m in an aqueous solution using iron (III) chloride as a polymerization initiator and a dopant is described in Journal of Chemical Society Chemical Communication (J. Chem. Soc., Chem, Commu
n.) 1987, p. 288. However, what is produced by this is ultrafine particles composed only of a conductive polymer, and it does not form composite particles with a semiconductor. In addition, as an example of applying such chemical polymerization, an example of forming a polypyrrole thin film on polystyrene latex having a carboxy group or a sulfone group is described in, for example, "Basics and Applications of Conducting Polymers" (APC 1988). Although it is described on page 132, this is not intended to form composite ultrafine particles with a semiconductor, nor is it intended to form composite particles with a semiconductor.

[0009]

Inorganic compounds, especially composite particles of a semiconductor and an organic compound, especially nanometer-sized composites, are expected to have new performance. There was no example.

That is, the present invention has an object to create a novel ultrafine particle material of a composite of an inorganic compound and an organic compound capable of expressing an electronic function, and further to create the particle material having a controlled particle size. To do.

[0011]

Means for Solving the Problems The inventors of the present invention have made earnest studies on the purpose of controlling the particle size distribution of semiconductor particles. Surprisingly, a novel compound consisting of a semiconductor and a conductive polymer has been obtained. We came to discover particles and their manufacturing method. Furthermore, they have found that the particle size distribution can be controlled. In the presence of the monomer that is the raw material of the conductive polymer,
It is a composite particle composed of semiconductor particles and a conductive polymer, which is manufactured by irradiating semiconductor particles with light, and a method for manufacturing the same. Furthermore, in the presence of a monomer that is a raw material of the conductive polymer,
The present invention relates to a composite particle of semiconductor particles and a conductive polymer, which is manufactured by synthesizing semiconductor particles, growing them, and simultaneously irradiating them with light, and a manufacturing method thereof. In particular, these manufacturing methods are applied even to nanometer-sized particles, that is, ultrafine particles.

That is, more specifically, the present invention relates to a composite particle composed of semiconductor particles and a conductive polymer, which is produced by irradiating semiconductor particles with light in the presence of a monomer which is a raw material of a conductive polymer. Yes, also, in the presence of a monomer that is a raw material of the conductive polymer, while synthesizing semiconductor particles, while growing this is a composite particle composed of semiconductor particles and a conductive polymer produced while irradiating light at the same time, Further, the semiconductor particles are composite particles composed of semiconductor particles that are ultrafine particles and a conductive polymer, and the semiconductor particles are composite particles that are chalcogenide semiconductor particles, and also the semiconductor particles according to any one of the above. A molded body of a composition comprising composite particles of a conductive polymer, and also
It is a molded product of a composition obtained by further dispersing composite ultrafine particles of semiconductor particles and a conductive polymer in a polymer.

The present invention is also a method for producing composite particles composed of a semiconductor and a conductive polymer, which comprises irradiating the semiconductor particles with light in the presence of a monomer which is a raw material for the conductive polymer. In the presence of a monomer which is a raw material of a conductive polymer, a method for producing a composite particle consisting of a semiconductor and a conductive polymer, in which semiconductor particles are synthesized, and while being grown, the semiconductor particles are irradiated with light at the same time. A method for producing a composite particle comprising semiconductor particles and a conductive polymer, which are ultrafine particles, and a method for producing a composite particle, wherein the semiconductor particle is a chalcogenide semiconductor particle, and also a semiconductor particle and a conductive polymer. A method for forming a molded body, which comprises molding a composition comprising composite particles, wherein the composite ultrafine particles of semiconductor particles and a conductive polymer are further dispersed in a polymer. And composition, a method of manufacturing a molded article for molding this is. Hereinafter, the content of the present invention will be described in detail.

As described above, the present invention relates to a novel material, which is a composite particle of semiconductor particles and a conductive polymer, and more particularly to an ultrafine particle of a composite of semiconductor particles and a conductive polymer. The particles referred to herein may be particles having a particle diameter of 100 micrometers or less, and ultrafine particles have a particle diameter of 1 to 100 nanometers, and more preferably 1 to 20 nanometers. It has an average particle diameter. As a means for measuring the particle size and composition of the particles, a generally known method, for example, a method using a microscope or light scattering may be used, and for very small particles such as ultrafine particles, a transmission electron microscope is used. Observation and analysis, powder X-ray diffraction, optical absorption spectrum measurement and the like can be used.

The semiconductor in the semiconductor particles in the present invention means a group IV element such as silicon or germanium, an oxide semiconductor such as TiO ₂ or ZnO, or GaAs or I.
III-V group compound semiconductors such as nP and InSb, II-VI group compound semiconductors such as CdS, CdSe, ZnSe and CdTe, and I-groups such as CuCl and CuBr.
Examples include Group VII compound semiconductors.

In the present invention, the conductive polymer may be a polymer showing conductivity, a polymer showing conductivity by doping, or a polymer showing conductivity by irradiation with light. Specifically, for example, condensed aromatic hydrocarbons such as polyacene, polyacetylenes such as polyacetylene and phenyl groups and silyl groups, and substituted polyacetylenes having an alkyl group such as polydiacetylenes, polypyrrole and poly N-alkylpyrrole, Mainly composed of heterocyclic five-membered ring polymers such as polythiophene, poly (3-alkylthiophene), poly (3,4-dimethylthiophene), polyfuran, polyselenophene, and polytellurophene, and polythiophene vinylene. Fused ring polymers such as copolymers or complex polymers, polyazulene, polyindene, polyindole, polypyrene, polycarbazole, etc., polyparaphenylene, polyphenylene sulfide, polynaphthylene, polyphenylenes such as polyanthracene, polyphenylene, etc. Polyphenylene vinylenes such as vinylene, main chain conjugated organic polymers such as polyaniline and polypyridazine, side chain conjugated organic polymers such as polyvinylcarbazole, and polyphthalocyanines such as polyphthalocyanine and ferrocene based polymers. I can give you.

More preferably, polypyrrole or poly N-
Heterocyclic five-membered ring polymers such as alkylpyrrole, polythiophene, poly (3-allylthiophene), poly (3,4-dimethylthiophene), polyfuran, polyselenophene, and polytellurophene, and polythiophene vinylene. A condensed ring-based polymer such as copolymer or composite polymer mainly composed of polyazulene, polyindene, polyindole, polypyrene, polycarbazole, polyparaphenylene, polyphenylene sulfide,
Examples thereof include polyphenylenes such as polynaphthylene and polyanthracene, polyphenylene vinylenes such as polyphenylene vinylene, and main chain conjugated organic polymers such as polyaniline and polypyridazine.

In a broad sense, a large amount of fine particles of carbon black, metal, metal oxide, etc. dispersed and mixed in a polymer medium is sometimes referred to as a composite conductive polymer, which has been conventionally used as a conductive material. However, in the present invention, such a composite is not meant as a conductive polymer.
Needless to say, even if the composite composition obtained in the present invention can be used as a conductive material, it does not fall within the scope of such a technique.

In the present invention, semiconductor particles are irradiated with light in the presence of a monomer which is a raw material for a conductive polymer to produce composite particles composed of a semiconductor and a conductive polymer. Moreover,
In the presence of a monomer that is a raw material for a conductive polymer, first, semiconductor particles are synthesized, and while growing, composite particles composed of a semiconductor and a conductive polymer whose particle size and particle size distribution are controlled while being irradiated with light at the same time. To manufacture. In particular, ultrafine particles can be applied as particles.

The present invention is characterized in that semiconductor particles themselves forming a composite with a conductive polymer are irradiated with light to form ultrafine particles of the composite. In particular, it is characterized in that composite particles having controlled particle size and particle size distribution are manufactured by synthesizing semiconductor particles and manufacturing composite particles while growing. Therefore, the semiconductor particles may be manufactured in advance, or may be synthesized and grown at the same time when the composite particles are manufactured.

Any light source for irradiating light may be used as long as it can excite semiconductor particles. In order to obtain composite particles having a controlled particle size, preferably, the vicinity of the absorption edge of the semiconductor particles is monochromatic light or a constant wavelength. It is desirable to irradiate light of longer wavelength. As such a light source, a xenon lamp,
Examples thereof include a mercury lamp, a tungsten lamp, a lamp having a wavelength cut filter applied thereto, and a laser light source such as an argon ion laser or a dye laser.

It is preferable that the intensity of the irradiation light is stronger so that it can compete with the reaction for producing semiconductor particles to produce a conductive polymer, but if the intensity of light is too high, other than the photoreaction that produces a conductive polymer. Since it may cause photoreaction such as other photodegradation, it is preferably 0.002W.
/ Cm ^{2 to 1} W / cm ² is desirable. Moreover, the wavelength of the light to be irradiated can be arbitrarily set depending on the type of the target semiconductor and the particle size to be controlled. One of the features of the present invention is that the particle size of the produced composite particles can be arbitrarily controlled by irradiating light with an arbitrary setting. However, it should be appreciated that the wavelength of light selected must be shorter than the absorption wavelength of the bulk semiconductor. Preferably 200 from the absorption end of the bulk semiconductor
Irradiate light with a short wavelength within nm.

In the present invention, the semiconductor particles are preliminarily produced by a generally known vapor phase production method, liquid phase production method, or production method in a solid containing a gas phase or a liquid phase. Good. For example, in the vapor phase, an evaporation condensation method such as a vapor deposition method in a gas or a laser evaporation method, a plasma C
A VD method, a CVD method such as a laser CVD method, or the like can be used. In the liquid phase, it can be produced by a coprecipitation method, a metal alkoxide method, a protective colloid method, or the like. Next, the semiconductor particles produced by these methods are taken out, and in the presence of the raw material monomer of the conductive polymer, light irradiation is carried out in a gas phase or a liquid phase, or in a solid containing a gas phase or a liquid phase to obtain a conductive polymer. Polymerization is initiated to form composite particles. The amount thereof is preferably about 0.1 g to 100 g / g particle.

In the present invention, semiconductor particles are synthesized,
A method of producing composite particles of a semiconductor and a conductive polymer while growing can also be adopted, but even in that case, in the vapor phase while irradiating with light, an evaporation condensation method such as a vapor deposition method in a gas or a laser evaporation method is used. , Plasma CVD method, CVD method such as laser CVD method and the like, and co-precipitation method in the liquid phase, metal alkoxide method, protective colloid method, etc. are used to grow semiconductor particles and to form composite ultrafine particles with conductive polymer. Can be manufactured. From the viewpoint of easy control of the reaction and mass productivity, a production method in a liquid phase such as a coprecipitation method, a metal alkoxide method, a protective colloid method and an organosol method can be mentioned as preferable examples.

The following is an example of a method for producing composite particles of a semiconductor and a conductive polymer in the simplest liquid phase, but it goes without saying that the present invention is not limited to this method.

First, the semiconductor raw material and the conductive polymer raw material are dissolved in a solvent. The amount of solvent is 1 when the semiconductor raw material concentration
It should be about 0 ^-6 mol / l to 10 ^-1 mol / l.
The non-aqueous solvent used is preferably a relatively polar non-aqueous solvent, specifically, for example, acetone, acetonitrile, benzonitrile, dimethylformamide, dimethylsulfoxide, chloroform, methanol, ethanol, dioxane, tetrahydrofuran. , Methyl ethyl ketone, etc., or a mixed solvent containing them is used.

As the semiconductor raw material, a metal compound soluble in the solvent used in the synthesis of semiconductor particles in such a liquid phase can be used. These metal compounds are
As described above, it is desirable that the solution has a concentration of preferably 10 ^-1 mol / l or less, more preferably 10 ^-6 mol / l to 10 ^-3 mol / l.

As the metal compound, for example, organic acid salts such as acetate, metal nitrates, perchlorates, alkoxides, acetylaceronates, halides and the like are used. Preferably, metal halides, metal nitrates, metal perchlorates, and metal acetates are used. These may contain water of crystallization.

As the metal species, a group III element such as Al, Ga, or In which forms a group III-V compound semiconductor, II-VI.
Group II elements such as Zn, Cd, and Hg that form group compound semiconductors, and Cu that form group I-VI and group I-VII compound semiconductors
Group I element such as P, which produces IV-VI group compound semiconductor
Examples include group IV elements such as b, Ti, and Sn.

As the monomer of the conductive polymer, the monomer of the corresponding polymer to be the composite particles is used. For example, for heteropyrrole members such as polypyrrole, poly N-alkylpyrrole, polythiophene, poly (3-alkylthiophene), poly (3,4-dimethylthiophene), polyfuran, polyselenophene, and polytellurophene. May be a corresponding pyrrole, N-alkylpyrrole, thiophene, 3-allylthiophene, 3,4-dimethylthiophene, furan, selenophene, or tellurophene, respectively. A copolymer mainly composed of a heterocycle such as polythiophene vinylene or For the composite polymers, thiophene vinylene or a copolymer and corresponding monomers may be mixed and used. Further, condensed ring polymers such as polyazulene, polyindene, polyindole, polypyrene, and polycarbazole include azulene, indene, indole, pyrene, carbazole, polyparaphenylene, polyphenylene sulfide, polynaphthylene,
For main chain conjugated organic polymers such as polyphenylenes such as polyanthracene, polyaniline and polypyridazine, benzene, benzene sulfide, naphthylene, anthracene, aniline and pyridazine may be used as monomers. The monomer concentration of the conductive polymer in the reaction solution is preferably 0.
The molar concentration is preferably 1 to 100 times, more preferably 1 to 50 times.

Next, the solution in which the semiconductor raw material and the conductive polymer monomer are dissolved is irradiated with light. The irradiation light is desirably applied to the entire reaction solution. Further, when the reaction progresses to form composite particles of a semiconductor and a conductive polymer, light is absorbed by the generated composite particles, so that the optical density of the final product solution should be 3 or less in terms of absorbance. If the raw material concentration is adjusted in advance or the optical distance of the reactor for light irradiation is adjusted in advance, the reaction can be suitably carried out. The light intensity of light irradiation is preferably 0.002
Is preferably a ^{W / cm 2 ~1W / cm 2} , the type of semiconductor wavelength of interest of the irradiated light, can be arbitrarily set by the particle size to control the absorption end of preferably a bulk semiconductor Light of a specific short wavelength within 200 nm or light on the longer wavelength side is irradiated using a cut filter or the like.

When a metal compound is used as a semiconductor in the state of being irradiated with light, for example, CdS, CdSe,
Taking as an example the case of forming composite particles using II-VI group compound semiconductors such as ZnSe and CdTe, suitable hydrides such as hydrogen sulfide gas and hydrogen selenide gas and organic chalcogenides such as bistrimethylsilylsulfur are suitable. By adding a chalcogenizing agent to the raw material solution irradiated with light, semiconductor particles can be generated and grown, and at the same time, composite ultrafine particles of a semiconductor and a conductive polymer can be obtained. These reagents are preferably diluted with an inert gas such as helium or nitrogen or a solvent to control the reaction for producing semiconductor particles. The reaction gas concentration is preferably 10% or less by volume, more preferably 1% or less by volume. The flow rate of the diluted reaction gas may be an amount sufficient to allow the reaction to proceed steadily. When the reaction solution is 100 ml or less, usually 1 ml / min to 500 ml / min is preferably used.

The progress of this reaction can be observed by a method such as light absorption or quasi-elastic light scattering observation of particle size distribution. Based on these observations, the growth of semiconductor particles, the formation of a conductive polymer, and the formation of composite particles proceed, and the reaction is terminated when the particle growth is saturated. The produced solution may be purified by a method such as centrifugation or column chromatography. Although the details of the mechanism by which a composite particle of a semiconductor and a conductive polymer is obtained by such a reaction have not been clarified, the fact that the semiconductor is a particle, in particular, an ultrafine particle makes it possible to improve the adsorption ability of a monomer and a specific electron. It is presumed that the redox reaction with the monomer on the photoexcited surface of the semiconductor particle efficiently proceeds depending on the physical property, and as a result, the conductive polymer is produced.

In particular, in the case where a monomer, which is a raw material of a conductive polymer, and a semiconductor raw material coexist, and semiconductor particles are generated and grown while irradiating with light having a certain wavelength or longer, the semiconductor raw material or the semiconductor It is considered that the nuclei of fine particles grow while maintaining interaction with the monomer such as adsorption. In particular, in the case of semiconductor ultrafine particles, the light absorption wavelength grows toward the long wavelength side as it grows due to the confinement effect of the minute space, and only particles that have grown to a certain particle size can absorb light, so a certain particle size can be absorbed. Only semiconductor particles of a diameter can produce a conductive polymer and form a composite. In this way, it is presumed that composite particles of a semiconductor and a conductive polymer with controlled particle size and distribution are formed.

The solution containing the composite particles of the semiconductor particles and the electroconductive polymer thus obtained may be used for a desired purpose by dissolving other components as it is, and the solvent may be evaporated or distilled under reduced pressure. It can be removed as a powder by a method such as. The powder of the composite particles of the semiconductor and the conductive polymer taken out in this way is compressed, heat-compressed, melted, or re-dispersed in a solvent, and a film such as a film is formed by a method such as screen printing, dip coating, or spin coating. The composition can be formed into a conductive polymer composition in which semiconductor particles are dispersed. Further, the composition thus formed can be etched into a desired form by a generally known method such as dry etching.

The composite particles of the semiconductor and the conductive polymer of the present invention may be added with a small amount (doping) of other components, if necessary. The small amount addition (doping) may be performed on the produced composite particles, or may be performed during the production. There are many unclear points about what kind of structural change occurs in semiconductors, conductive polymers, and their composites when added in small amounts (doping). It is thought that a coordinated arrangement may occur.

In the composite particles of the semiconductor and the conductive polymer, for example, in order to improve the electric conductivity, an electron-accepting substance (acceptor) such as iodine, bromine, arsenic pentafluoride, Lewis acid, or a transition metal halide is added thereto. Alkyl metals such as sodium and sodium, and an electron donating substance (donor) such as alkylammonium may be added in a small amount (doping). As a method of adding a small amount (doping),
It can be performed by a general method such as gas phase doping, liquid phase doping, electrochemical drop doping, ion implantation, light or radiation induced doping.

The composite ultrafine particles of a semiconductor and a conductive polymer taken out as a solution or powder should be treated with a small amount of addition (doping) and then made into a composition in which the semiconductor particles are dispersed in the conductive polymer. But you can
Other polymers and components can be added to give the desired composition. This composition can be molded into a desired molded body. Needless to say, the desired composition can be obtained by adding other polymers or components without adding a small amount (doping) or the like. Further, as described above, the composition may be in the form of a liquid such as a coating liquid, and may be used by molding into a thin film, a multilayer film of these, a block, a lens, a fiber, a waveguide or the like.

Other polymers suitable for molding may be used according to the application and are not particularly limited. Specific examples include polymethylmethacrylate, polyethylmethacrylate and poly (2-hydroxyethyl). Methacrylate, polycarbonate, polystyrene, polyester, polyethylene terephthalate, polyvinyl chloride, polyether sulfone, polyacrylonitrile, a copolymer of vinyl chloride and vinyl acetate, a copolymer of styrene and acrylonitrile, etc. may be mentioned. It is also possible to re-dissolve with a photocurable resin, a thermosetting resin or another compatible resin to prepare a coating liquid for forming a thin film. Other components include, for example, holes such as amine compounds, electron transport materials, and surfactants.

[0040]

EXAMPLES The present invention will be described in more detail based on the following examples. Example 1 cadmium perchlorate hexahydrate _{(Cd (ClO 4) 2 ·} 6
H ₂ O) and aniline (C ₆ H ₅ NH ₂ ) respectively.
4 ml of an acetonitrile solution dissolved at a concentration of 0 × 10 ⁻³ mol / l and 4.0 × 10 ⁻² mol / l was put in a 1 cm square branched quartz cell, and the argon ion laser 45 was used.
Irradiation with a 7.9 nm oscillation line was performed. The amount of light applied to this solution was measured with a power meter and adjusted to 0.02 W / cm ² .

While irradiating the laser light in this way, a mixed gas prepared by diluting hydrogen sulfide gas with helium gas to 0.1 vol% was introduced into a solution stirred at a flow rate of 54 ml / min, When the reaction was carried out while measuring the light absorption spectrum, no change in the light absorption spectrum was observed in about 10 minutes. This was used as the end point of the reaction. The light absorption spectrum thus obtained is shown in FIG. That is, FIG. 1 is a visible / ultraviolet absorption spectrum of the composite ultrafine particle solutions obtained in Example 1 and Comparative Example 1 below, in which the horizontal axis represents the observed wavelength and the vertical axis represents the absorbance.
The solid line 1 shows the result of Example 1, and the dotted line 2 shows the result of Comparative Example 1 described below. Light absorption spectrum is 400 nm
There is an absorption shoulder in the vicinity, and a shape in which light absorption extends to a long wavelength is observed, which is considered to be light absorption derived from polyaniline which is a conductive polymer. A part of this solution was taken out and observed with a transmission electron microscope.
Particles having a core portion of 8 to 5.4 nanometers and an outer shell having a thickness of about 5 nanometers were observed.

Comparative Example 1 An experiment was conducted in the same manner as in Example 1 except that the argon ion laser beam was not irradiated. The solution thus obtained is yellow and its light absorption spectrum is shown as dotted line 2 in FIG. In the light absorption spectrum, there is an absorption shoulder near 400 nm, but the shape of light absorption extending to the long wavelength seen in Example 1 was not observed. That is, Example 1
The long-wavelength light absorption derived from polyaniline, which was observed in 1., is not observed, and it can be seen that polyaniline is not formed when light irradiation is not performed.

A part of this solution was taken out and observed by a transmission electron microscope. As a result, the particle size was 4.9 to 15.6.
Nanometer particles were observed, but no outer shell structure was observed. That is, it is understood that in the absence of light irradiation, particles of the complex of cadmium sulfide and polyaniline are not formed.

Example 2 0.14 g of sodium hydroxide was dissolved in 120 ml of a methanol-ethanol mixed solvent (mixing volume ratio 5: 7),
Polyvinylpyrrolidone (Wako Pure Chemical Industries, Ltd.)
-30) 1.0 g was added and dissolved. This solution was placed in a 300 ml Pyrex glass flask equipped with a reflux tube and refluxed under a nitrogen stream while heating with a water bath, and the solution temperature was kept at 70 to 71 ° C. 0.66 g of zinc nitrate hexahydrate (Zn (NO ₃ ) ₂ .6H ₂ O) was added here.
First, 4 ml of a solution dissolved in ml of ethanol was added to a refluxing flask. Next, 2 ml of distilled water was added to the remaining 1 ml of the zinc nitrate hexahydrate solution, and the mixture was added to the refluxing flask, and then refluxing was continued under a nitrogen stream for 10 hours.

After stopping the reflux and lowering the temperature of the solution,
0.31 g of aniline was added to the flask, a magnetic stirrer was added, and the light of a 250 W high-pressure mercury lamp was irradiated through a Pyrex glass flask while stirring. The solution turned golden and the absorption spectrum was measured. As a result, a spectrum in which absorption appeared at a long wavelength having an absorption shoulder at 350 nm was obtained. A part of this solution was taken out and observed with a transmission electron microscope. As a result, it was found that the core part having a particle size of 6.0 to 10.1 nm and the thickness were about 1
Particles with an outer shell of 2 nanometers were observed.

Comparative Example 2 An experiment was conducted in the same manner as in Example 1 except that light irradiation with a high pressure mercury lamp was not performed. The solution thus obtained is almost colorless and its optical absorption spectrum is
There is a shoulder of absorption near 0 nm and light absorption rises from around 370 nm. In Example 1, it was almost the same as the light absorption spectrum of the solution before light irradiation.

When a part of this solution was taken out and observed with a transmission electron microscope, the particle size was 6.0-1.
Particles of 0.1 nanometer were observed, but no outer shell structure was observed. That is, when there is no light irradiation,
It can be seen that particles of the complex of zinc oxide and polyaniline were not formed.

[0048]

INDUSTRIAL APPLICABILITY The present invention provides a novel material, which is a composite particle composed of a semiconductor and a conductive polymer, particularly a composite ultrafine particle. Also provided are composite particles, especially composite ultrafine particles, which are composed of a high-quality semiconductor and a conductive polymer having a controlled particle size and particle size distribution.

[Brief description of drawings]

FIG. 1 is a visible / ultraviolet absorption spectrum of composite ultrafine particle solutions obtained in Example 1 and Comparative Example 1.

[Explanation of symbols]

1 Solid line showing the results of Example 1 2 Dotted line showing the result of Comparative Example 1

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI H01B 1/00 H01B 1/20 Z H01L 31/08 B01J 13/02 A 51/10 H01L 31/08 T // H01B 1/20 (56) References JP-A-5-93076 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B01J 19/12 B01J 2/00-2/30 H01B 1/00-1 / 24 B01J 13/00-13/22

Claims (12)

(57) [Claims] 1. Composite particles composed of semiconductor particles and a conductive polymer, which are produced by irradiating semiconductor particles with light in the presence of a monomer that is a raw material of a conductive polymer. 2. The composite particle comprising the semiconductor particle and the conductive polymer according to claim 1, wherein the semiconductor particle is a semiconductor particle synthesized and grown while being irradiated with light. 3. The composite particles comprising the semiconductor particles according to claim 1 and the conductive polymer, wherein the semiconductor particles are ultrafine particles. 4. A composite particle comprising the semiconductor particle according to any one of claims 1 to 3 and a conductive polymer, wherein the semiconductor particle is a chalcogenide semiconductor particle. 5. A molded product of a composition containing the composite particles according to claim 1. 6. A molded article of a composition containing composite particles, which is obtained by dispersing the composite particles according to any one of claims 1 to 4 in a polymer. 7. A method for producing composite particles composed of a semiconductor and a conductive polymer, which comprises irradiating the semiconductor particles with light in the presence of a monomer which is a raw material for the conductive polymer. 8. The method for producing composite particles according to claim 7, wherein the semiconductor particles are semiconductor particles synthesized and grown while being irradiated with light. 9. The method for producing composite particles according to claim 7, wherein the semiconductor particles are ultrafine particles. 10. The method for producing composite particles according to claim 7, wherein the semiconductor particles are chalcogenide semiconductor particles. 11. A method for producing a molded article of a composition containing the composite particles according to claim 7. 12. A method for producing a molded article of a composition containing composite particles, comprising the composite particles according to claim 7 dispersed in a polymer.